1. Welcome to the Solar System
A Celestial Alignment
Why do they line up?
Image from: ganymede.nmsu.edu/tharriso/ast110/class05.html

2. Moons also orbit in the same plane
Jupiters equitorial bands show the eliptic (tilt = 0)
Image:

3. Orbits in the Ecliptic
This also includes ring systems!

4. The Solar Disk
Seen from a 100 AU
Solar system is a dusty disk

5. The Layout of the Solar System
Large bodies in the Solar System have orderly motions
planets orbit counterclockwise in same plane
orbits are almost circular
the Sun and most planets rotate counterclockwise
most moons orbit counterclockwise

6. The Layout of the Solar System
Planets fall into two main categories
Terrestrial (i.e. Earth-like)
Jovian (i.e. Jupiter-like or gaseous)

7. Mars
Neptune
Terrestrial
Jovian

8. Mars and Neptune to Scale

11. The Layout of the Solar System
Swarms of asteroids and comets populate the Solar System

12. Comets are found in two main Zones:
The Kuiper Belt
The Oort Cloud
The Oort cloud goes from 5000 to 50,000 AU or further!

13. When Comets are disturbed from their orbits..
They end up in eliptical orbits..
Encounters with Jovian Planets speed them up or slow them down…
The Oort Cloud is the “shell” of slow moving comets at aphelion
Speeds at aphelion might be a few cm/sec!
If and when they approach the Sun, the move much faster!

14. They Also Grow Tails…
Image from APOD (credit and copyright Jimmy Westlake)

15. Not everything fits perfectly
The line between planet and comet is not clear!
Pluto, Quoar, Viruna, Xenia, and Sedna are all Kuiper Belt objects (KBO’s)
Or the Solar system has at least 13 planets…or 8 major planets and 5 + minor planets!
Check out:
Artists conception of Xenia and the Solar System…100AU from Sun. Note the 44 degree tilt of orbit.

16. Quoar’s Orbit

17. Meet some new family members

18. How out does the solar system go?

19. A Few (more) Exceptions to the Rules…
Both Uranus & Pluto are tilted on their sides.
Venus rotates “backwards” (i.e. clockwise).
Triton orbits Neptune “backwards.”
Earth is the only terrestrial planet with a relatively large moon.
Density decreases from Mercury outward, but Earth is more dense than any other planet!

20. A Brief Tour of the Solar System -- Motions

21. Density of water is defined as 1 g/cm3.
What is density?
density = mass/volume
typical units: [ g/cm3]
Density of water is defined as 1 g/cm3.
Density of typical Metal is 10 g/cm3

22. A Brief Tour of the Solar System – Composition

23. A Brief Tour of the Solar System – Summary

24. Spacecraft Missions--categories
Flyby – spacecraft “flies by” a world just once
Orbiter – spacecraft orbits the world it studies
longer-term study is allowed
Lander/Probe – spacecraft lands on the surface of the world or plunges through its atmosphere
Sample Return – spacecraft returns to Earth with a sample of the world it has studied
These types of mission are listed in order of increasing cost.

25. Missions to Other Worlds
Upcoming missions:
Deep Impact:
Crashed into comet Temple 1 July
Mars Reconnaissance Orbiter: Low orbit..one meter surface resolution! Launched Aug 12..Arives Nov 06.
New Horizons: Orbiter to Pluto/Charon leave 2006 – arrive 2020!

26. Highlights of coming attractions
Mercury’s extreme days and nights, tall steep cliffs, and large iron content
Venus’s extreme greenhouse effect
Earth as an oasis of life
Evidence on Mars for a past, wet era
Jupiter’s hydrogen and helium atmosphere and its many moons
Saturn’s rings and its moon Titan, which is larger than Mercury
Uranus and its moons: a system tipped on its side compared to the other planets
Neptune’s largest moon, Triton, with nitrogen “geysers” and a “backward orbit”
Pluto as a member of the family of Minor Planets!